Evaluate the relationship between dissemination of the results of the Coronary Drug Project (CDP) and current clinical practice. Provide data on the current use of aspirin in clinical practice for the treatment of post-myocardial infarction patients. Provide data on the use of aspirin in myocardial infarction patients after the results of the Aspirin Myocardial Infarction Study (AMIS) have been published. Provide analysis of evaluation and findings, including discussion of strengths and weaknesses of methods of dissemination and their impact on clinical practice.